<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="js/vue.js"></script>
</head>
<body>
    <div id="app">
           请选择性别
           <input type="radio" value="0" v-model="sex">女
           <input type="radio" value="1" v-model="sex">男
           <h3>选择的类别为{{sex}}</h3> 
    </div>
</body>
<script>
    new  Vue({
        el:"#app",
        data:{
            sex:0
        },
        watch:{
            sex(){
            } 
        }
    })


</script>
</html>